1. Field of the Invention
The present invention relates to the improvement of a valve device comprising: a valve chamber having an inlet port at one end and a valve seat at the other end; a valve housing containing the valve chamber; the valve chamber accommodating a spherical valve element which performs opening and closing operation to the valve seat, and a valve spring which urges the valve element in a closing direction; and a push rod which penetrates a center hole of the valve seat and pushes the valve element in an opening direction.
2. Description of the Related Art
Such a valve device has been already known as disclosed in Japanese Patent Application Laid-Open No. 2002-310328.
In such a conventional valve device, a spherical valve element is loosely accommodated in a valve chamber so that a passage is secured between the valve element and an inner peripheral surface of the valve chamber to provide communication between an inlet port and a valve seat. Therefore, the valve element may laterally oscillate at the time of an opening and closing operation. Hence, this is a cause of accelerating the abrasion of not only the valve element and the valve seat, but also a push rod which makes the valve element open.